Projectdetails

Small shorebirds breeding in the High Arctic have very high thermoregulatory and incubation costs. Sanderlings Calidris alba are known to have a breeding system in which females sometimes lay two clutches of four eggs. The male incubates the first clutch, the female incubates the second clutch herself. The advantage for double-clutching individuals is obvious: a higher reproductive success. However, this breeding strategy also entails substantial costs for both parents. First, the female has to lay an additional set of eggs soon after having laid a first complete clutch. Secondly, two birds have to separately take care of the incubation of a clutch and chick guarding. In the proposed research we wish to investigate the possible relation between immune response and breeding effort at a study site in Northeast Greenland with a known Sanderling population that shows both the single- and the double-clutch strategy. We hypothesise that Sanderlings might be able to make such large investments in reproduction by economising on their immune system in the relatively parasite- and disease-poor High Arctic environment. Only high-quality birds that are free of parasites are expected to be able to down-regulate their immune system. In their wintering habitat in Western Europe and especially tropical Africa, Sanderlings scavenge between decaying organic material and need to maintain high levels of immunity. The contrast in breeding strategies within a single Arctic bird species enables us to gain knowledge on fundamental questions about disease risk and immune function of Arctic shorebirds that spend part of their life in Western European marine habitats and may yield important information on the spread of diseases by migratory birds.

Artikelen

• (2007). De drieteenstrandloper is een kwetsbare honkvaste globetrotter (the Sanderling is a vulnerable solid base globetrotter). Vogelnieuws. pp. 14-15